The stock market's wild ride over the past week has been "the biggest exercise in sheer unadulterated speculation" Jack Bogle has ever seen in his more than 60 years in the business, the index mutual fund pioneer said Friday.

His advice to investors—don't do anything right now.

"It's just speculators not speculating on what they think is going to happen but what they think other speculators think is going to happen," the founder of the Vanguard Group said in an interview with CNBC's "Power Lunch."

"This speculative binge that we're seeing here … has nothing to do with the fundamentals behind the long-term value of equities in particular, which are created by the values of corporations, earnings and dividends, and reinvestment in the business."